This is propertyWrapper for threadsafe access to webSocket instance

import Foundation

@propertyWrapper
struct Atomic<Value> {

    private var value: Value
    private let lock = NSLock()

    init(wrappedValue value: Value) {
        self.value = value
    }

    var wrappedValue: Value {
      get { return load() }
      set { store(newValue: newValue) }
    }

    func load() -> Value {
        lock.lock()
        defer { lock.unlock() }
        return value
    }

    mutating func store(newValue: Value) {
        lock.lock()
        defer { lock.unlock() }
        value = newValue
    }
}

This is implementation WSS

import NIO
import NIOHTTP1
import NIOWebSocket
import WebSocketKit

final class WSS: ACWebSocketProtocol {

  var url: URL
  private var eventLoopGroup: EventLoopGroup
  @Atomic var ws: WebSocket?

  init(stringURL: String, coreCount: Int = System.coreCount) {
      url = URL(string: stringURL)!
      eventLoopGroup = MultiThreadedEventLoopGroup(numberOfThreads: coreCount)
  }

  var onConnected: ((_ headers: [String : String]?) -> Void)?
  var onDisconnected: ((_ reason: String?) -> Void)?
  var onCancelled: (() -> Void)?
  var onText: ((_ text: String) -> Void)?
  var onBinary: ((_ data: Data) -> Void)?
  var onPing: (() -> Void)?
  var onPong: (() -> Void)?

  func connect(headers: [String : String]?) {

      var httpHeaders: HTTPHeaders = .init()
      headers?.forEach({ (name, value) in
          httpHeaders.add(name: name, value: value)
      })
      let promise: EventLoopPromise<Void> = eventLoopGroup.next().makePromise(of: Void.self)

      WebSocket.connect(to: url.absoluteString,
                        headers: httpHeaders,
                        on: eventLoopGroup
      ) { ws in
          self.ws = ws

          ws.onPing { [weak self] (ws) in
              self?.onPing?()
          }

          ws.onPong { [weak self] (ws) in
              self?.onPong?()
          }

          ws.onClose.whenComplete { [weak self] (result) in
              switch result {
              case .success:
                  self?.onDisconnected?(nil)
                  self?.onCancelled?()
              case let .failure(error):
                  self?.onDisconnected?(error.localizedDescription)
                  self?.onCancelled?()
              }
          }

          ws.onText { (ws, text) in
              self.onText?(text)
          }

          ws.onBinary { (ws, buffer) in
              var data: Data = Data()
              data.append(contentsOf: buffer.readableBytesView)
              self.onBinary?(data)
          }

      }.cascade(to: promise)

      promise.futureResult.whenSuccess { [weak self] (_) in
          guard let self = self else { return }
          self.onConnected?(nil)
      }
  }

  func disconnect() {
      ws?.close(promise: nil)
  }

  func send(data: Data) {
      ws?.send([UInt8](https://raw.github.com/nerzh/Action-Cable-Swift/master/data))
  }

  func send(data: Data, _ completion: (() -> Void)?) {
      let promise: EventLoopPromise<Void>? = ws?.eventLoop.next().makePromise(of: Void.self)
      ws?.send([UInt8](https://raw.github.com/nerzh/Action-Cable-Swift/master/data), promise: promise)
      promise?.futureResult.whenComplete { (_) in
          completion?()
      }
  }

  func send(text: String) {
      ws?.send(text)
  }

  func send(text: String, _ completion: (() -> Void)?) {
      let promise: EventLoopPromise<Void>? = ws?.eventLoop.next().makePromise(of: Void.self)
      ws?.send(text, promise: promise)
      promise?.futureResult.whenComplete { (_) in
          completion?()
      }
  }
}    

import Foundation
import Starscream

class WSS: ACWebSocketProtocol, WebSocketDelegate {

    var url: URL
    var ws: WebSocket

    init(stringURL: String) {
        url = URL(string: stringURL)!
        ws = WebSocket(request: URLRequest(url: url))
        ws.delegate = self
    }

    var onConnected: ((_ headers: [String : String]?) -> Void)?
    var onDisconnected: ((_ reason: String?) -> Void)?
    var onCancelled: (() -> Void)?
    var onText: ((_ text: String) -> Void)?
    var onBinary: ((_ data: Data) -> Void)?
    var onPing: (() -> Void)?
    var onPong: (() -> Void)?

    func connect(headers: [String : String]?) {
        ws.request.allHTTPHeaderFields = headers
        ws.connect()
    }

    func disconnect() {
        ws.disconnect()
    }

    func send(data: Data) {
        ws.write(data: data)
    }

    func send(data: Data, _ completion: (() -> Void)?) {
        ws.write(data: data, completion: completion)
    }

    func send(text: String) {
        ws.write(string: text)
    }

    func send(text: String, _ completion: (() -> Void)?) {
        ws.write(string: text, completion: completion)
    }

    func didReceive(event: WebSocketEvent, client: WebSocket) {
        switch event {
        case .connected(let headers):
            onConnected?(headers)
        case .disconnected(let reason, let code):
            onDisconnected?(reason)
        case .text(let string):
            onText?(string)
        case .binary(let data):
            onBinary?(data)
        case .ping(_):
            onPing?()
        case .pong(_):
            onPong?()
        case .cancelled:
            onCancelled?()
        default: break
        }
    }
}